Depends on the size of the tank!
The tank isnt large enough for a severum alone, let alone any tankmates, minimum size tank for a severum is IMO 75g, however, some will say 55g, either way, 42g is definately not large enough for long term health, growth and happiness.
In my opinion a 42g is fine for a young specimen with tankmates. A 75g tank with a 1" severum is a waste but please understand that as the fish grow so does the space they require!
Thats very true Wills, but there are exceptions. For example you buy a fish and the tank you want to put him wont work right now because he is to small and would get eaten. So you put him in a smaller tank until he gets a little bigger then move him to the bigger tank. One key thing to this is I already had the bigger tank though, so if you dont have a bigger tank and just "plan" on getting a bigger one might not be a good idea cause things happen.In my opinion a 42g is fine for a young specimen with tankmates. A 75g tank with a 1" severum is a waste but please understand that as the fish grow so does the space they require!
Well yeah but thats the same with any fish. A 1" aripama would be okay in a 42g but you house a fish in a tank suitable for life not for size when bought.

sev id say no aswell, my chocolate cichlid is in a 150us and i wouldnt keep him in much smaller and hes 8inch at present,,,,
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